WASHINGTON (CBS/AP) — Republican Pennsylvania Sen. Pat Toomey was one of six Senate Republicans to join Democrats to proceed with former President Donald Trump’s second impeachment trial. The Senate voted mostly along party lines 56-44.

Toomey was joined by Sens. Bill Cassidy of Louisiana, Susan Collins of Maine, Lisa Murkowski of Alaska, Ben Sasse of Nebraska and Mitt Romney of Utah.

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Trump was impeached by the House of Representatives for “incitement of insurrection” for his actions leading up to last month’s deadly U.S. Capitol riot.

On Sunday, Toomey told CNN it’s “very unlikely” the Senate votes to convict Trump.

“You did have 45 Republican senators vote to suggest that they didn’t think it was appropriate to conduct a trial, so you can infer how likely it is that those folks will vote to convict,” Toomey told CNN’s Jake Tapper on “State on Union.”

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The senator, who has said he is not going to run for reelection after his term ends in 2022, was one of five Republicans who joined Democrats in tabling an effort to force a vote on the constitutionality of the trial last month. He told Tapper that he stands by his previous remark that Trump “committed impeachable offenses.”

“I think it is constitutional. I think it’s clearly constitutional to conduct a Senate trial with respect to an impeachment. In this case the impeachment occurred prior to the President leaving office,” Toomey said. “I stand by everything I’ve said, Jake. I still think the best outcome would have been for the President to resign. Obviously he chose not to do that.”

He added that as a juror in the impeachment trial, “I’m going to listen to the arguments on both sides and make the decision that I think is right.”

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